Samsung Galaxy S9 - calls going blank

[AJ9]

Hi:

I have a Samsung Galaxy S9 (SM-G960W) that I have had on PM since brand new for about 11 months now. It was working OK till about August end. After that, I'm having major issues with my voice calls. In the middle of talking, the calls will completely blank out, I can't hear the other side and they can't hear me, sometimes for up to 20 seconds. And then the voice will resume. The calls are still connected. The issue happens anywhere - at my work, outside, inside in my house. The network signal is OK.

Here is what I have tried so far:

- Taken the sim out and put it in another phone for 2 weeks, no voice call issues.

- Put the sim back in my S9, set the network mode to WCDMA/GSM only, keep data off during voice calls, issue persists.

- manually create the APN and select that, issue persists.

I reported it to the mods and they opened a ticket for it. I did receive a callback from one mod, and while talking to them, this issue was experienced. They were able to diagnose it as my device.

Since it's still under warranty, I took it to a Samsung Authorized Service Center - Fonelab in STC. They changed the main board and gave it back to me. I have it back for 2 weeks now and the issue is still there. I have contacted Samsung support directly and they have asked me to take it to another Authorized Service Center. I am going to do that this week and see if that makes any difference.

Does anyone have any ideas/suggestions on how to solve this issue? It was working up to August without any such issues.

Thanks.

[AJ9]

Yes it is updated and running the latest build from 1-Oct-2019. I already noted that in one of my previous posts. Thanks.

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@Lemony_Snicket wrote:

This sounds like a software problem.  Check out this post.  Try to make sure the phone is running the latest software.

https://www.sammobile.com/2018/05/04/new-galaxy-s9-update-fixes-call-issues/

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[Lemony_Snicket]

This sounds like a software problem.  Check out this post.  Try to make sure the phone is running the latest software.

https://www.sammobile.com/2018/05/04/new-galaxy-s9-update-fixes-call-issues/

[AJ9]

Good suggestion, have not tried that, will try that for a couple of days and report back. Thanks.

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@totalUser wrote:

Does it happen when you use headphones? It's possible that mic contact went, in that case headphones wouldn't be affected.

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[totalUser]

Does it happen when you use headphones? It's possible that mic contact went, in that case headphones wouldn't be affected.

[AJ9]

No I didn't install any new apps before this started happening.

I have tried calls while there are apps running in the background, and also with no apps running in the background. It is the same result. Besides this phone has enough resources (cpu/ram) to handle voice calls and apps running at the same time.

The apps that I have installed are minimal - messages (for sms), whatsapp and facebook messenger.

What you're suggesting to run the phone without any installed apps is not an option for me. Not sure how it's different than these apps closed and not running in the background. These apps use minimal resources afaik.

Thanks.

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@popping wrote:

@AJ9 

Did you installed any new app(s) before this is happening?

An app is using up the CPU time while you are on a call.

Factory reset your phone and test it without any installed apps for couple of days.

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[popping]

@AJ9 

Did you installed any new app(s) before this is happening?

An app is using up the CPU time while you are on a call.

Factory reset your phone and test it without any installed apps for couple of days.

[will13am]

I have never experienced this type of behavior with any phone that I have ever used on this network.  The family all use different phones and brands.  Definitely something not right with the phone.  It is interesting that a main board replacement which probably replaces everything except the screen and battery did not resolve the problem.  Hopefully someone else with a S9 can weigh in with their user experience. 

[AJ9]

Yes to network settings reset and factory reset. It has the latest O/S updates installed. Yes am aware that apn settings are for data and not voice calls. Thanks.

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@Dunkman wrote:

@AJ9 

Have you tried network reset?  factory reset? update operating system of phone?

Likely your phone needs ot be repaired again.

Since the PM Sim card work in another phone, unlikely to be PM Service issue.  APN settings important for data, not voice calls.  

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[Dunkman]

@AJ9 

Have you tried network reset?  factory reset? update operating system of phone?

Likely your phone needs ot be repaired again.

Since the PM Sim card work in another phone, unlikely to be PM Service issue.  APN settings important for data, not voice calls.